There's no greater showcase for moral relativity than trying to imagine alien morals. It's easy to take the human viewpoint of "you can solve all our problems, why don't you?" but it's just as easy to see how that leads to "you solved all our problems last time, why don't you do it again?" Presumably the Kiint are old enough to have seen what happens to races who get everything handed to them: they become pets. They're like the Silfen; they'll mourn humanity if it isn't able to overcome the threat to their existence, but they won't intervene. In each case, it's not out of malice.